The Smart Effector has about 12 sq cm of strain gauge traces (less the hole for the hot end), plus another 12 sq cm of circuitry and connectors. We can't really reduce that. So we need an area of around 24 sq cm plus a little extra for mounting holes. Maybe we could make it 70mm wide, but not much narrower than that.

I made a new version, with all connectors on top of the PCB, to make more space for the fans. I also did a hotend with the lathe. It works great. I load everything on Thingiverse when everything is ready.